Countable Connected Spaces
نویسنده
چکیده
Introduction, Let © be the class of all countable and connected perfectly separable Hausdorff spaces containing more than one point. I t is known that an ©-space cannot be regular or compact. Urysohn, using a complicated identification of points, has constructed the first example of an ©-space. Two ©-spaces, X and X*, more simply constructed and not involving identifications, are presented here. The space X* is a connected subspace of X and contains a dispersion point; tha t is, the subspace formed from X* by removing this one point is totally disconnected.
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